Would these 3 fish be compatible?

This is a discussion on Would these 3 fish be compatible? within the Characins forums, part of the Freshwater and Tropical Fish category; -->
So, at the moment I have 3 Silver Tipped Tetra in a 20 gallon with a pleco. I'm looking to add 2 more of ...

Agree. And as I mentioned in my response to your PM, there is not a lot of space in a 20g high. A group of 7-8 Silvertip Tetra plus some substrate fish (group of corys for instance) would be it. Six ST and six neon tetra could manage with live plants and weekly water changes.